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| author | John Hurley <john.hurley@netronome.com> | 2019-07-07 17:01:56 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-07-09 05:50:13 +0300 |
| commit | d27cf5c59a12f66425df29cd81f61aa73ef14ac1 (patch) | |
| tree | 200e7e737082e2e2a129789edc00cddaab20aea8 /net/core | |
| parent | ed246cee09b9865145a2e1e34f63ec0e31dd83a5 (diff) | |
| download | linux-d27cf5c59a12f66425df29cd81f61aa73ef14ac1.tar.xz | |
net: core: add MPLS update core helper and use in OvS
Open vSwitch allows the updating of an existing MPLS header on a packet.
In preparation for supporting similar functionality in TC, move this to a
common skb helper function.
Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/skbuff.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 8c00be4d8919..93443a01ab39 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -5532,6 +5532,39 @@ int skb_mpls_pop(struct sk_buff *skb, __be16 next_proto) EXPORT_SYMBOL_GPL(skb_mpls_pop); /** + * skb_mpls_update_lse() - modify outermost MPLS header and update csum + * + * @skb: buffer + * @mpls_lse: new MPLS label stack entry to update to + * + * Expects skb->data at mac header. + * + * Returns 0 on success, -errno otherwise. + */ +int skb_mpls_update_lse(struct sk_buff *skb, __be32 mpls_lse) +{ + int err; + + if (unlikely(!eth_p_mpls(skb->protocol))) + return -EINVAL; + + err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); + if (unlikely(err)) + return err; + + if (skb->ip_summed == CHECKSUM_COMPLETE) { + __be32 diff[] = { ~mpls_hdr(skb)->label_stack_entry, mpls_lse }; + + skb->csum = csum_partial((char *)diff, sizeof(diff), skb->csum); + } + + mpls_hdr(skb)->label_stack_entry = mpls_lse; + + return 0; +} +EXPORT_SYMBOL_GPL(skb_mpls_update_lse); + +/** * alloc_skb_with_frags - allocate skb with page frags * * @header_len: size of linear part |